/*
 * Copyright (c) 2001-2004 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Hessian", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.caucho.hessian.io;

import java.util.*;
import java.util.zip.*;

import java.io.*;

import com.caucho.hessian.io.*;

public class Deflation extends HessianEnvelope {
	public Deflation() {
	}

	public Hessian2Output wrap(Hessian2Output out) throws IOException {
		OutputStream os = new DeflateOutputStream(out);

		Hessian2Output filterOut = new Hessian2Output(os);

		filterOut.setCloseStreamOnClose(true);

		return filterOut;
	}

	public Hessian2Input unwrap(Hessian2Input in) throws IOException {
		int version = in.readEnvelope();

		String method = in.readMethod();

		if (!method.equals(getClass().getName()))
			throw new IOException("expected hessian Envelope method '"
					+ getClass().getName() + "' at '" + method + "'");

		return unwrapHeaders(in);
	}

	public Hessian2Input unwrapHeaders(Hessian2Input in) throws IOException {
		InputStream is = new DeflateInputStream(in);

		Hessian2Input filter = new Hessian2Input(is);

		filter.setCloseStreamOnClose(true);

		return filter;
	}

	static class DeflateOutputStream extends OutputStream {
		private Hessian2Output _out;
		private OutputStream _bodyOut;
		private DeflaterOutputStream _deflateOut;

		DeflateOutputStream(Hessian2Output out) throws IOException {
			_out = out;

			_out.startEnvelope(Deflation.class.getName());

			_out.writeInt(0);

			_bodyOut = _out.getBytesOutputStream();

			_deflateOut = new DeflaterOutputStream(_bodyOut);
		}

		public void write(int ch) throws IOException {
			_deflateOut.write(ch);
		}

		public void write(byte[] buffer, int offset, int length) throws IOException {
			_deflateOut.write(buffer, offset, length);
		}

		public void close() throws IOException {
			Hessian2Output out = _out;
			_out = null;

			if (out != null) {
				_deflateOut.close();
				_bodyOut.close();

				out.writeInt(0);

				out.completeEnvelope();

				out.close();
			}
		}
	}

	static class DeflateInputStream extends InputStream {
		private Hessian2Input _in;

		private InputStream _bodyIn;
		private InflaterInputStream _inflateIn;

		DeflateInputStream(Hessian2Input in) throws IOException {
			_in = in;

			int len = in.readInt();

			if (len != 0)
				throw new IOException("expected no headers");

			_bodyIn = _in.readInputStream();

			_inflateIn = new InflaterInputStream(_bodyIn);
		}

		public int read() throws IOException {
			return _inflateIn.read();
		}

		public int read(byte[] buffer, int offset, int length) throws IOException {
			return _inflateIn.read(buffer, offset, length);
		}

		public void close() throws IOException {
			Hessian2Input in = _in;
			_in = null;

			if (in != null) {
				_inflateIn.close();
				_bodyIn.close();

				int len = in.readInt();

				if (len != 0)
					throw new IOException("Unexpected footer");

				in.completeEnvelope();

				in.close();
			}
		}
	}
}
